Read the threads about regional rail or NSRL. The problem is going to be capacity on the NEC with Amtrak looking for more train slots. Something in the commuter rail world needs to go away to allow Indigo frequencies and more NEC slots for Amtrak. Needham is the logical candidate (two service expansions options, Orange or Green.)

^ the Southeast Corridor from Forest Hills through Ruggles and Back Bay already has as many tracks as it will ever hold. That is the section where adding new Amtrak trips will eventually squeeze out commuter rail trips.

__________________"Trying to solve congestion by making roadways wider is like trying to solve obesity by buying bigger pants."--Charles Marohn

^ the Southeast Corridor from Forest Hills through Ruggles and Back Bay already has as many tracks as it will ever hold. That is the section where adding new Amtrak trips will eventually squeeze out commuter rail trips.

Yes. And the NEC FUTURE study predicts a grim future where Needham thru slots will be forced onto 1 bidirectional track to stay out of the way of Amtrak and Providence/Stoughton growth on the other tracks...meaning there can never be simultaneous Needham inbounds and outbounds at the same time. Doubly grim because the only mechanism for not cutting service levels is running a portion of the schedule as a shuttle to/from Forest Hills only...which will catastrophically destabilize an already overloaded Orange Line at FH.

As is, you can never increase service levels commensurate with the Regional Rail levels envisioned for all other 128-reaching lines such as Fairmount and Worcester Line to Riverside, meaning it is consigned to being the forever-gimp of the RER system.

Those are the reasons it must be expunged from the commuter rail system, and why the T is finally acknowledging in public via the RER study concepts that they may have no choice in the matter but to swap modes.

Now...the Newton Highlands-to-128 portion that doesn't have any rail transit has had ample demand studies done showing a dam about to burst on the Highland Ave./Needham St. corridor begging for a major transit expansion. A demand explosion that's also dragging Kendrick down with it. The GL stop proposed New England Business Center on the branch is aimed to be paired with a new circulator bus shuttle around the vast office park to help tame the redirected car congestion post- 128 widening. And on the other side of 128, Gould St./TV Place/Muzi Ford is another massive redev parcel and the most likely pick for the park-and-ride stop (NEBC is on a quiet side street, so will have the shuttle bus but not native parking). The new Kendrick exit sets up highway access via Hunting Rd. direct-connecting to Gould to help load-spread the Pn'R crowds from the Gould stop's lot/garage between both exits.

^^That's^^ just the new upside to be tapped before you even hit Needham Heights and start mode-changing the 3 existing downtown stops. But it all directly addresses these new 128 traffic patterns.

If it were possible, how many tracks would be needed to handle all of the Amtrak, Orange Line and commuter rail traffic?

Four RR tracks + two Orange. And that SW Corridor tunnel widening was already studied for South Coast Rail. It priced out at billions of dollars with mass destruction to SW Corridor Park during the widening, and was rejected as completely infeasible for its unfavorable impacts.

To ease the traffic problem you need to clear out a couple branch schedules. Needham is the worst and most urgent because it makes all local stops, stays entirely within the unexpandable tunnel footprint, and is facing hard loss of frequencies in 20 years. There is no perma-fix except converting it to rapid transit. There's barely anything you can do to even rearrange deck chairs to bum a slot, because any new slot you come up with Providence is going to be the hungriest mouth to feed.

Franklin will eventually need to start having more Forge Park slots run via the Fairmount Line, where Foxboro service will run from Day 1...then eventually run 100% via Fairmount (which has the capacity to give). But that relocation is a less urgent need than Needham because Amtrak plans to reinstate Track 4 between Forest Hills and Readville to allow them ample passing room to get off to the races...and Franklin schedules today very rarely stop at Hyde Park, so they get off the Corridor decently quick. Eventually when Amtrak is revved up to 2040 Superduper HSR service levels, the only T services using the NEC should be Providence and Stoughton/South Coast. That'll be manageable enough to run full RER-frequency service that co-mingles peacefully with Amtrak. But it'll take a net reduction of 2 branch schedules.

Note also that neither Stoughton nor Providence are acceptable candidates for the Fairmount Line because of the need to re-engage Amtrak NEC dispatch at Readville for the trip to Canton and beyond. For schedule management's sake it's best to keep those two permanently on the Corridor with no reverse-branching, while Franklin is hands-down the one to relocate to Fairmount because its whole trip to Forge Park would then stay under unified T dispatch.

The official completion of the project is Spring 2019, however it looks like they're pretty much done and the latest update from MassDOT said the contractor is on their punch list of leaving the site.

Overall it looks great and a nice roadway upgrade project. The frontage roads around Highland Ave were a smart idea and make navigating the area a lot easier.

Does anyone know why they did not add a deceleration lane on the northbound side for the Dedham/Needham Route 135 Exit? I get that there is a town forest on one side, so probably a straight off ramp was out of the question, but with the prison and dpw yard on the other side, I think they could have found the space. You go down a steep hill for over a mile and then into a circa 1950 tight off ramp. I find that incredibly dangerous and something that should have been fixed.

Does anyone know why they did not add a deceleration lane on the northbound side for the Dedham/Needham Route 135 Exit? I get that there is a town forest on one side, so probably a straight off ramp was out of the question, but with the prison and dpw yard on the other side, I think they could have found the space. You go down a steep hill for over a mile and then into a circa 1950 tight off ramp. I find that incredibly dangerous and something that should have been fixed.

According to AASHTO, at 450 ft. that decel lane complies fully with Interstate Highway standards for a 25 MPH exit ramp off a 65 MPH mainline. So by-the-book there's nothing whatsoever deficient about it.

It just may seem that way vs. the adjacent ramps like Kendrick/Highland that are extremely overbuilt because of their volumes. 135 really doesn't get a lot of traffic.